This application addresses Challenge Area #15:Translational Science and Specific Challenge Topic, 15-HD-102: Pelvic Pain. We propose to characterize the pain with menses and noncyclic pelvic pain in women with uterine leiomyomas at baseline and following minimally-invasive treatment. Our submission also addresses Challenge Area #5: Comparative Effectiveness Research and Specific Challenge Topic, 05- EB-103 Comparative Effectiveness of Non-Invasive Ultrasound Techniques. We propose a randomized clinical trial comparing symptomatic relief following two minimally invasive treatments for uterine leiomyomas: uterine artery embolization (UAE) and MRI guided focused ultrasound (MRgFUS). Uterine leiomyomas (fibroids or myomas) are diagnosed in one quarter of all women and up to 75 % of African-American women. The direct health care costs attributable to leiomyomas exceed $2.1 billion annually1. However, our work reported that indirect costs (disability and absenteeism) are equivalent to direct costs for women with clinically significant fibroids ($11,720 vs. $11,752/woman/year) 2. This is a significant increase in indirect costs for women with symptomatic fibroids compared to control women when controlled for demographic and case mix factors ($11,752 vs. $8083, p<0.0001)2. Thus, understanding and addressing the symptoms of clinically-significant uterine fibroids and particularly pain is important in optimizing treatment outcomes and controlling health care costs from a societal perspective. Despite their prevalence, fibroid symptomatology is still incompletely understood. Myomas are reported to cause a number of symptoms including heavy or prolonged menstrual bleeding, pelvic pressure, pain with menses (dysmenorrhea) and bowel and bladder dysfunction. However leiomyoma pain has never been studied with the standard instrument for assessing and quantitating pain, the McGill Pain Questionnaire (MPQ) 3. Moreover, most leiomyoma studies have not differentiated between pain with menses and non cyclic pelvic pain. One expert review of leiomyomas suggests the presence of noncyclic pelvic pain should prompt investigation of other disease processes 4. Yet studies of 3 year outcomes following uterine artery embolization treatment (UAE) suggest that 83% of women have long term improvement in pelvic pain 5. This study will also track changes in pelvic pain and other symptomatic outcomes following treatment with two minimally-invasive FDA-approved techniques for leiomyoma treatment uterine artery embolization (UAE) and MRI-guided focused ultrasound surgery (MRgFUS). UAE and MRgFUS differ significantly in approach, mechanism of action and side effects and they have never been compared in a randomized clinical trial. UAE employs angiographic occlusion of the uterine arteries as a global uterine treatment leading to ischemic necrosis. Following UAE, women appear to have more pain in the immediate postoperative period, but studies document decreased pelvic pain during long term follow-up. In contrast, MRgFUS targets the interstitium of individual fibroids and produces thermoablative coagulative necrosis. This myoma-specific approach causes less postoperative pain and allows for outpatient treatment but is less comprehensive and may lead to less long term symptomatic improvement. We therefore propose the PAM Trial: Pain Assessment for Myomas, a randomized clinical trial treating 220 racially-diverse women with symptomatic uterine leiomyomas with UAE or MRgFUS and following them for a minimum of 6 months. This funding mechanism will cover costs from baseline to 6 months for each subject and we are actively pursuing public/private partnerships to allow long term follow up. A racially diverse cohort of subjects will be achieved by recruiting through Mayo Clinic and Duke University. PUBLIC HEALTH RELEVANCE: Uterine leiomyomas or fibroids are an extremely common disease in reproductive age women and particularly African-American women. Fibroids are the leading cause of hysterectomy, yet the amount of pelvic pain they cause has not been clearly documented. This study will characterize the amount of pelvic pain women with fibroids have with their menstrual periods and at other times in the month and whether pain is decreased by uterine artery embolization (UAE) and magnetic resonance guided focused ultrasound (MRgFUS), two minimally-invasive treatments for fibroids